The break-in at Buckingham Palace, in which a man was arrested in one of the
state rooms after scaling a 12ft fence, is the latest in a series of
security scares involving the Royal Family.

* In February this year a man was stopped by police using a Taser stun gun after holding a knife to his neck outside Buckingham Palace.

Talhat Rehman, 54, broke from a crowd of tourists in the middle of the Changing of the Guard ceremony, holding one blade to his chest and another to his throat.

As an officer tried to intervene, he lunged at him waving both knives and was shot with the stun gun before being arrested and taken away in a police van. He later pleaded guilty to two counts of having a knife in public.

* In March 2011 a car carrying the Prince of Wales and the Duchess of Cornwall was mobbed by demonstrators who had split from a protest against higher university tuition fees.

Camilla was visibly distressed after being poked in the ribs with a stick through an open window in the distinctive Rolls-Royce Phantom VI as she and Charles travelled to the Royal Variety Performance at the London Palladium.

* In 2003, comedian Aaron Barschak managed to get into Prince William's 21st birthday party at Windsor Castle.

The self-styled "comedy-terrorist" set off a series of alarms and was caught on CCTV before he joined 300 guests at the bash and was removed.

* In 1994, student David Kang charged at Charles while firing a starting pistol during a ceremony in Sydney, Australia.

Kang was wrestled to the ground by New South Wales premier John Fahey and another man, while Charles was praised for his calm reaction.

* In 1982 Michael Fagan evaded guards to get inside the Queen’s private chambers while she was still in bed.

The unemployed father of four, 31, spent around 10 minutes talking to the Queen after he climbed over the palace walls and up a drainpipe.

The Queen managed to raise the alarm when Fagan asked for a cigarette, allowing her to call for a footman who held him until police arrived.

Fagan had set off an alarm, but a member of staff assumed it was faulty and switched it off. He managed to enter the bedroom affter the police officer outside went off duty and before his replacement arrived.

* in 1981, six blank shots were fired from the crowd while the Queen rode during the Trooping the Colour ceremony.

The Queen's horse was startled but she managed bring it back under control while police rushed to grab the shooter.

* In 1974, Princess Anne was the target of an apparent kidnap attempt in The Mall near Buckingham Palace.

Four people, including her bodyguard, Jim Beaton, were injured after shots were fired when their car was forced to halt by another vehicle which blocked their route.

A police officer chased the driver, Ian Ball, and brought him to the ground before arresting him.